This project is evaluate the ecological health of New Bedford Harbor, MA (NBH), an EPA designated Superfund Site. Building on previous research that focused on distribution of metals in NBH sediments and the interactions between metals and metals and microbial communities, we propose to evaluate both organic and inorganic contaminant accumulation in the biota. Accumulation alone, however, does not provide evidence of ecological effect. We will therefore examine physiological and biochemical responses in the macrobiota to pollutants, including effects on their endocrine systems. We will also continue to develop microbial community biomarkers of contaminant exposure, based on induction of genetic responses. The ultimate aim is to provide a suite of exposure biomarkers that can be used to evaluate ecosystem health. We propose to integrate ecotoxicology, molecular microbiology and geochemistry to develop techniques reflecting the relationship between environmental contaminants and their bioavailability to higher organisms. This will be accomplished through a series of laboratory and field studies designed to identify candidate biomarkers and relate their frequency of expression in field samples with contaminant speciation (Project 9) and biological uptake measurements.